Blue_MiSfit
11th July 2004, 02:55
This is an offshoot of my earlier posting about another "pass" to further enhance quality.
Basically this idea involves making a more informed decision as to which custom quantization matrix (cqm) to use when encoding your film. The basic algorithm is as follows:
1) break the stream into "scenes", with a "scene" being defined as the span of time between sharp changes in the video image - thus a sort of "rough I-frame estimate"
2) encode each "scene" with each cqm you want to compare at your target bitrate
3) compare each version of each scene to one another with an SSIM test (manual visual comparison is far too time consuming for this process)
4) whichever cqm has the highest number of "wins" is the cqm you should use for the movie
theoretically anyway...
I know SSIM is not as good at analyzing quality as is a manual visual study. However, visually scanning each clip is far too time consuming for the user (you). SSIM is accurate enough for making decisions IMHO, I mean XviD uses PSNR internally for its encoding process - and SSIM is supposed to be better at analyzing video than PSNR anyway isn't it?
Lol... I'm kind of talking out of my ass here but whatever...
just some food for thought
~MiSfit
Basically this idea involves making a more informed decision as to which custom quantization matrix (cqm) to use when encoding your film. The basic algorithm is as follows:
1) break the stream into "scenes", with a "scene" being defined as the span of time between sharp changes in the video image - thus a sort of "rough I-frame estimate"
2) encode each "scene" with each cqm you want to compare at your target bitrate
3) compare each version of each scene to one another with an SSIM test (manual visual comparison is far too time consuming for this process)
4) whichever cqm has the highest number of "wins" is the cqm you should use for the movie
theoretically anyway...
I know SSIM is not as good at analyzing quality as is a manual visual study. However, visually scanning each clip is far too time consuming for the user (you). SSIM is accurate enough for making decisions IMHO, I mean XviD uses PSNR internally for its encoding process - and SSIM is supposed to be better at analyzing video than PSNR anyway isn't it?
Lol... I'm kind of talking out of my ass here but whatever...
just some food for thought
~MiSfit